Sustained delivery of MMP-9 siRNA via thermosensitive hydrogel accelerates diabetic wound healing.

Excessive expression of matrix metalloproteinase 9 (MMP-9) impedes healing of diabetic chronic wounds, thus wound dressing that could effectively inhibit the expression of MMP-9 offers significant clinical translation for diabetic wound healing. Herein, a hybrid hydrogel dressing was developed for localized and sustained delivery of MMP-9 siRNA (siMMP-9). siMMP-9 was complexed with Gly-TETA (GT), the GT/siMMP9 complex was then loaded into a thermosensitive hydrogel based on Pluronic F-127 (PF) and methylcellulose (MC). In vitro, this hybrid hydrogel dressing exhibited negligible cytotoxicity, prolonged the release of GT/siMMP-9 for up to 7 days, and significantly reduced MMP-9 expression. In vivo assessment in diabetic rats demonstrated that hydrogel provided localized and sustained delivery via the thermosensitive controlled release of entrapped GT/siMMP-9 into wound tissues for 7 days, resulting in dramatic MMP-9 silencing which significantly improved diabetic wound closure. This hybrid hydrogel dressing exhibited excellent biocompatibility, with no observed systemic toxicity in rats. Taken together, the hybrid hydrogel dressing may constitute an effective and biocompatible means of enhancing diabetic wound healing through effective silencing of the MMP-9 gene, and this hydrogel delivery system also offers a platform for in vivo delivery of siRNA for the treatment of other diseases.

Association of gonadal hormones and sex hormone binding globulin with risk of diabetes: A cohort study in middle-aged and elderly Chinese males.

AIM: Late-onset hypogonadism in men is related to the development of diabetes. The association of gonadal hormones, sex hormone binding globulin with diabetes has been studied in various studies. However, there is no cohort study on the relationship between gonadal hormone, sex hormone binding globulin and diabetes in Chinese. We aimed to provide an insight into the possible association in middle-aged and elderly Chinese males. METHODS: We included a population sample of 673 subjects aged 40 years or older. Total testosterone (TT), sex hormone binding globulin (SHBG), follicle-stimulating hormone (FSH) and luteinising hormone (LH) were detected. The homeostasis model assessment of insulin resistance (HOMA-IR) was calculated to estimate insulin sensitivity. Diabetes was diagnosed according to the 2010 American Diabetes Association criteria. RESULTS: With an average follow-up time of 3.2 ± 0.5 years, 9.8% of participants had developed diabetes. The prevalence of diabetes was decreased according to increasing SHBG quartiles (Q1:13.1%, Q2: 12.0%, Q3: 11.2%, Q4: 3.0%, P for trend < .0001) and TT (Q1:16.0%, Q2: 7.9%, Q3: 9.0%, Q4: 6.4%, P for trend < .0001). The ORs of diabetes for increasing SHBG quartiles were 4.52 (95% CI 1.40-14.57), 4.32 (95% CI 1.33-14.06), 3.89 (95% CI 1.21-12.50) and 1.00 (reference) respectively. But the odds of prevalent diabetes were not increased in different quartiles of TT, FSH and LH. In subgroup analyses, the relationship between SHBG and risk of incident diabetes was significantly increased in the population aged over 60, without insulin resistance and with eGFR < 90 mL/min per 1.73 m2 . CONCLUSIONS: Compared with gonadal hormones, a lower level of SHBG is independently associated with the risk of diabetes in middle-aged and elderly Chinese males.

Obesity-associated secondary hypogonadism in young and middle-aged men in Guangzhou: A single-centre cross-sectional study.

AIM: Male obesity-associated secondary hypogonadism (MOSH) is becoming a public health issue. We aimed to know MOSH among young and middle-aged men in our hospital, to analyse their sex hormones and other index, and to determine leptin as a risk factor for MOSH. METHODS: In total, 258 men (ages ranging from 20 to 60, mean 38 ± 15) were enrolled in this study, and 242 of these men had their complete data, body mass index (BMI), waist circumference and sex hormones retrospectively investigated. The leptin and lipid levels were also evaluated, and comparisons were made between young (20-39 years old) and middle-aged (40-60 years old) men. RESULTS: Among all the participants, 7 were thin, with a BMI < 18.5 kg/m2 , 95 had a normal BMI (18.5 ≤ BMI < 23.9 kg/m2 ), 87 (35.9%) were overweight (24 ≤ BMI ≤ 27.9 kg/m2 ) and 53 (21.9%) were obese (BMI ≥ 28 kg/m2 ), 173 (71.5%) had a waist sized ≥ 85 cm. Among the 242 men, 104 (43%) had hypogonadism (TT ≤ 331.412 ng/dL). Compared with the men of normal weight, the level of testosterone of the obese men decreased (P = .006), while the level of serum lipids (including total cholesterol, TG and low-density lipoprotein cholesterol, P < .05) was elevated, higher UA, FSH and leptin were also present in the obese men. There were 83 (34.2%) men with MOSH. Compared with middle-aged men with MOSH, the FSH in young men was significantly reduced (P < .05); no significant increase in estradiol was observed in the MOSH group. The leptin levels in the MOSH group were significantly higher than those in the hypogonadism only group (P < .001). CONCLUSION: Obesity increases the prevalence of hypogonadism. The decrease in testosterone levels in young men maybe due to inhibition of the hypothalamic pituitary gonadal axis. Leptin is an independent risk factor for MOSH.

Hyperbranched cationic polysaccharide derivatives for efficient siRNA delivery and diabetic wound healing enhancement.

Gene vectors are important for successful siRNA delivery. Four types of hyperbranched cationic polysaccharide derivatives (HCP) were synthesized by conjuncting 1,2-ethylenediamine (EDA) and diethylenetriamine (DETA) with glycogen or amylopectin respectively and named as G-EDA, G-DETA, A-EDA and A-DETA. The efficiency and safety of these HCPs to deliver siRNA were explored in vitro and in vivo. Our results showed that HCPs could form complexes with siRNA. All HCP/siRNA exhibited negligible cytotoxicity. Compared with A-EDA and A-DETA, G-EDA and G-DETA could carry much more siRNA into cells and then escape from endosomes. The delivery of MMP-9 siRNA (siMMP-9) by G-EDA and G-DETA significantly inhibited MMP-9 in HaCaT cells. Wound models in diabetic rats demonstrated that treatment of G-EDA/siMMP-9 could potently knock down MMP-9 of skin wound tissues and then enhanced wound healing. In summary, this study provided an effective and safe approach for siRNA delivery in vitro and in vivo.

Naturally-occurring bacterial cellulose-hyperbranched cationic polysaccharide derivative/MMP-9 siRNA composite dressing for wound healing enhancement in diabetic rats.

The anomalous high expression of matrix metalloproteinase 9 (MMP-9) is one important factor that impedes diabetic wound healing. Therefore, inhibition of MMP-9 expression in a diabetic wound could be a feasible method to promote wound healing. In this study, we studied the possibility of self-therapy using wound dressings that contain bacterial cellulose-hyperbranched cationic polysaccharide (BC-HCP) derivatives that encapsulate siRNA (BC-HCP/siMMP-9) and have controlled release properties. Herein, we used four HCPs (Gly-DMAPA, Gly-D4, Amyp-DMAPA, Amyp-D4) as gene carriers. Our results showed that all HCP derivatives were minimally toxic to cells in vitro, while the cationic properties of HCP could be used as a complexation agent for MMP-9 siRNA (siMMP-9). Upon exposure to bacterial cellulose (BC), the BC slowly released HCP/siMMP-9. The released siMMP-9 effectively reduced the gene expression and protein levels of MMP-9 in a human immortalized epithelial cell line (HaCAT) and in diabetic rat wounds. Inhibition of MMP-9 in the wounds of diabetic rats resulted in a significant enhancement of wound healing, suggesting that the BC-HCP/siMMP-9 composite dressing could be used as a safe and effective dressing to promote wound healing in diabetic rats. STATEMENT OF SIGNIFICANCE: In this work, we evaluated the possibility of using bacterial cellulose-hyperbranched cationic polysaccharide derivatives (BC-HCP) as a self-therapeutic wound dressing with siRNA encapsulated and controlled release properties. Our results showed that the BC-HCP/siMMP-9 composite dressing slowly released HCP/siMMP-9. The released siMMP-9 effectively reduced the gene expression and protein level of MMP-9 in human immortalized epithelial cell line and in the wound of diabetic rats. The BC-HCP/siMMP-9 composite dressing promoted diabetic wound healing by the unique nanostructure of BC and by releasing siMMP-9 for specific MMP-9 inhibition. Therefore, it could be used as a safe and effective dressing to promote wound healing in diabetic rats. This is the first evidence on the study of using BC as a dressing composite by encapsulating HCP/siRNA complexes for efficient RNAi gene silencing for better wound healing in diabetic rats.

Endothelial cell-derived small extracellular vesicles suppress cutaneous wound healing through regulating fibroblasts autophagy.

Diabetic foot ulcer is a life-threatening clinical problem in diabetic patients. Endothelial cell-derived small extracellular vesicles (sEVs) are important mediators of intercellular communication in the pathogenesis of several diseases. However, the exact mechanisms of wound healing mediated by endothelial cell-derived sEVs remain unclear. sEVs were isolated from human umbilical vein endothelial cells (HUVECs) pretreated with or without advanced glycation end products (AGEs). The roles of HUVEC-derived sEVs on the biological characteristics of skin fibroblasts were investigated both in vitro and in vivo We demonstrate that sEVs derived from AGEs-pretreated HUVECs (AGEs-sEVs) could inhibit collagen synthesis by activating autophagy of human skin fibroblasts. Additionally, treatment with AGEs-sEVs could delay the wound healing process in Sprague-Dawley (SD) rats. Further analysis indicated that miR-106b-5p was up-regulated in AGEs-sEVs and importantly, in exudate-derived sEVs from patients with diabetic foot ulcer. Consequently, sEV-mediated uptake of miR-106b-5p in recipient fibroblasts reduces expression of extracellular signal-regulated kinase 1/2 (ERK1/2), resulting in fibroblasts autophagy activation and subsequent collagen degradation. Collectively, our data demonstrate that miR-106b-5p could be enriched in AGEs-sEVs, then decreases collagen synthesis and delays cutaneous wound healing by triggering fibroblasts autophagy through reducing ERK1/2 expression.

Spectroscopic investigation of a hyperbranched cationic amylopectin derivative as a multi-guest molecular host for targeted delivery of a photosensitizer to pancreatic cancer cells.

To increase pancreatic tumor-targeted phototoxicity of photosensitizers, a hyperbranched cationic amylopectin derivative conjugated with 3-(dimethylamino)-1-propylamine (DMAPA-Amp) was invevstigated as a multi-guest molecular host for the targeted delivery of a photosensitizer to human pancreatic cancer (Panc-1) cells. We selected protoporphyrin IX (PpIX) and folic acid as a photosensitizer and a tumor-targeting factor, respectively. The complexation mechanism of DMAPA-Amp with PpIX and folic acid was characterized using NMR spectroscopy including 1H NMR, two-dimensional diffusion ordered spectroscopy (2D DOSY) NMR, fluorescence and UV-vis spectroscopy. The results indicated that the DMAPA-Amp derivative could serve as a host for the encapsulation of two guests, PpIX and folic acid, through intermolecular interactions. The complex showed high phototoxicity against Panc-1 cells, and its folic-acid-mediated cancer-cell-targeting property was confirmed by laser confocal microscopy and flow cytometry analysis. We provide a method to study hyperbranched cationic polymer-based complexes containing multiple guests, which could facilitate the design of multi-functional complexes in the drug delivery field.

[Diagnostic criteria for late-onset hypogonadism: A preliminary study].

OBJECTIVE: To determine the stability of androgen indexes by analyzing the relationship of androgen indexes with the results of late-onset hypogonadism (LOH) questionnaire investigations, and offer some reference for the application of the diagnostic criteria for LOH released by The Chinese Society of Andrology in 2009. METHODS: This study included 1 003 males aged 40 years or older who had accomplished the questionnaires of Androgen Deficiency in Aging Males (ADAM), Aging Males' Symptoms Scale (AMS), and International Index of Erectile Function-5 (IIEF-5). We evaluated the correlation of androgen indexes with the results of the questionnaire investigation, repeated the examination of androgen indexes for the subjects with total testosterone (TT) ≤11.5 nmol/L after an average of 1.5 years, and analyzed the factors inducing changes of androgen indexes. RESULTS: Free testosterone index (FTI) ≤ 0.42 (OR, 1.369) and calculated free testosterone (cFT) ≤ 0.3 nmol/L (OR, 1.302) were considered as the risk factors of LOH in AMS, and so were testosterone secretion index (TSI) ≤ 2.8 nmol/IU (OR, 1.679) and cFT ≤ 0.3 nmol/L (OR, 1.371) in IIEF-5. Paired t-test on the results of the examination performed twice showed significant differences in the levels of TT, TSI, cFT, and FT (P<0.05). CONCLUSIONS: Decreased testosterone may cause the diversity of LOH symptoms and hence the fluctuation of androgens. Therefore, the diagnosis of LOH depends on androgen indexes, varied symptoms in the questionnaires, and relief of the symptoms after testosterone therapy.